Build (method = -2) #dp: 38082 Step-3' Graph: 352 vertices and 1049 arcs (0.33s) Step-4' Graph: 44 vertices and 433 arcs (0.33s) #V4/#V3 = 0.12 #A4/#A3 = 0.41 Ready! (0.33s) Optimize a model with 124 rows, 434 columns and 1218 nonzeros Presolve removed 4 rows and 4 columns Presolve time: 0.01s Presolved: 120 rows, 430 columns, 1208 nonzeros Variable types: 0 continuous, 430 integer (232 binary) Found heuristic solution: objective 39.0000000 Optimize a model with 120 rows, 430 columns and 1208 nonzeros Presolved: 120 rows, 430 columns, 1208 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 4.870e+02 Factor NZ : 1.025e+03 Factor Ops : 1.430e+04 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 4.45770363e+02 -7.40804645e+02 1.41e+02 4.04e-02 2.94e+00 0s 1 9.28135584e+01 -2.03226793e+02 1.80e+00 2.22e-16 3.63e-01 0s 2 5.09027104e+01 -1.64214446e+01 9.07e-02 1.11e-16 7.83e-02 0s 3 2.58952567e+01 1.87888913e+01 3.30e-03 2.29e-16 8.07e-03 0s 4 2.50095009e+01 2.49552318e+01 2.03e-13 1.11e-16 6.17e-05 0s 5 2.50000001e+01 2.49999999e+01 1.21e-13 1.31e-16 1.77e-10 0s Barrier solved model in 5 iterations and 0.00 seconds Optimal objective 2.50000001e+01 Root relaxation: objective 2.500000e+01, 313 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 25.0000000 25.00000 0.0% - 0s Explored 0 nodes (390 simplex iterations) in 0.02 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 2.500000000000e+01, best bound 2.500000000000e+01, gap 0.0% Preprocessing time: 0.35 seconds Gurobi run time: 0.02 seconds Total run time: 0.36 seconds Objective: 25 Solution: 2 x [11, 24, 47, 55] 1 x [41, 45, 53, 59] 1 x [9, 14, 53, 59] 1 x [18, 26, 32, 50] 1 x [29, 37, 44, 58] 1 x [2, 2, 7, 43] 1 x [7, 10, 15, 37] 1 x [31, 31, 34, 35] 1 x [23, 30, 38, 42] 2 x [22, 46, 76, 80] 1 x [4, 8, 27, 28] 1 x [3, 5, 60, 79] 2 x [6, 57, 63, 70] 1 x [1, 69, 71, 77] 1 x [65, 68, 75, 78] 1 x [61, 62, 73, 74] 1 x [49, 56, 66, 72] 1 x [48, 52, 64, 67] 1 x [12, 17, 19, 58] 1 x [33, 36, 44, 54] 1 x [20, 25, 40, 51] 1 x [13, 16, 21, 39]